WIN32 how to cache drawing results to a bitmap? - c++

Because there are hover and leave events of the mouse in the interface, if re drawing in each leave event leads to a large amount of resource occupation, how to draw and cache it in memory only when the program is started or the interface is notified of changes, and send InvalidateRect() to directly use BitBlt mapping instead of re drawing in the rest of the time?
int dystat = 0;
int anistat = 0;
void CreatePanelDynamic(HWND h, HDC hdc, DRAWPANEL DrawFun, int Flag = 0)
{
//On hMemDC.
if (PanelID == PrevPanelID)
{
//
if (dystat == 0)
{
RECT rc;
GetClientRect(h, &rc);
BitBlt(hdc, 0, 0, rc.right - rc.left, rc.bottom - rc.top, in_ghdc, 0, 0, SRCCOPY); //by bitmap
}
else
{
_CreatePanel(h, hdc, DrawFun); //directly
dystat = 0;
}
anistat = 0;
}
if (PanelID != PrevPanelID) //animation
{
if (Flag == 0)
{
CreatePanelAnimation(h, hdc, DrawFun);
dystat = 1;
}
if (Flag == 1)
{
_CreatePanel(h, hdc, DrawFun);
dystat = 1;
}
PrevPanelID = PanelID;
anistat = 0;
}
}
My program is already using MemDC.

Related

Capture screenshot of minimized window [closed]

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I tried to follow the example found:
Capturing an image from a minimized window
My code:
#include <iostream>
#include <string>
#include <windows.h>
#include <gdiplus.h>
#pragma comment(lib, "gdiplus.lib")
#pragma warning(disable : 4996)
using namespace std;
using namespace Gdiplus;
int GetEncoderClsid(LPCWSTR format, CLSID* pClsid)
{
unsigned int num = 0, size = 0;
GetImageEncodersSize(&num, &size);
if (size == 0) return -1;
ImageCodecInfo* pImageCodecInfo = (ImageCodecInfo*)(malloc(size));
if (pImageCodecInfo == NULL) return -1;
GetImageEncoders(num, size, pImageCodecInfo);
for (unsigned int j = 0; j < num; ++j) {
if (wcscmp(pImageCodecInfo[j].MimeType, format) == 0) {
*pClsid = pImageCodecInfo[j].Clsid;
free(pImageCodecInfo);
return j;
}
}
free(pImageCodecInfo);
return -1;
}
int SaveScreenshot(string filename, ULONG uQuality, HWND hwnd) // by Napalm
{
ULONG_PTR gdiplusToken;
GdiplusStartupInput gdiplusStartupInput;
GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
HWND hMyWnd = hwnd;
//HWND hMyWnd = GetDesktopWindow();
RECT r;
int w, h;
HDC dc, hdcCapture;
int nBPP, nCapture, iRes;
LPBYTE lpCapture;
CLSID imageCLSID;
Bitmap* pScreenShot;
// get the area of my application's window
GetWindowRect(hMyWnd, &r);
dc = GetWindowDC(hMyWnd); // GetDC(hMyWnd) ;
w = r.right - r.left;
h = r.bottom - r.top;
nBPP = GetDeviceCaps(dc, BITSPIXEL);
hdcCapture = CreateCompatibleDC(dc);
// create the buffer for the screenshot
BITMAPINFO bmiCapture = { sizeof(BITMAPINFOHEADER), w, -h, 1, nBPP, BI_RGB, 0, 0, 0, 0, 0, };
// create a container and take the screenshot
HBITMAP hbmCapture = CreateDIBSection(dc, &bmiCapture, DIB_PAL_COLORS, (LPVOID*)&lpCapture, NULL, 0);
// failed to take it
if (!hbmCapture) {
DeleteDC(hdcCapture);
DeleteDC(dc);
GdiplusShutdown(gdiplusToken);
printf("failed to take the screenshot. err: %d\n", GetLastError());
return 0;
}
// copy the screenshot buffer
nCapture = SaveDC(hdcCapture);
SelectObject(hdcCapture, hbmCapture);
BitBlt(hdcCapture, 0, 0, w, h, dc, 0, 0, SRCCOPY);
RestoreDC(hdcCapture, nCapture);
DeleteDC(hdcCapture);
DeleteDC(dc);
// save the buffer to a file
pScreenShot = new Bitmap(hbmCapture, (HPALETTE)NULL);
EncoderParameters encoderParams;
encoderParams.Count = 1;
encoderParams.Parameter[0].NumberOfValues = 1;
encoderParams.Parameter[0].Guid = EncoderQuality;
encoderParams.Parameter[0].Type = EncoderParameterValueTypeLong;
encoderParams.Parameter[0].Value = &uQuality;
GetEncoderClsid(L"image/jpeg", &imageCLSID);
wchar_t* lpszFilename = new wchar_t[filename.length() + 1];
mbstowcs(lpszFilename, filename.c_str(), filename.length() + 1);
iRes = (pScreenShot->Save(lpszFilename, &imageCLSID, &encoderParams) == Ok);
delete pScreenShot;
DeleteObject(hbmCapture);
GdiplusShutdown(gdiplusToken);
return iRes;
}
int main() {
HWND hWnd;
hWnd = FindWindowA(NULL, "txt.txt - Bloco de Notas");
WINDOWPLACEMENT wp = { 0 };
wp.length = sizeof(WINDOWPLACEMENT);
GetWindowPlacement(hWnd, &wp);
ANIMATIONINFO ai = { 0 };
bool restoreAnimated = false;
if (wp.showCmd == SW_SHOWMINIMIZED)
{
ai.cbSize = sizeof(ANIMATIONINFO);
SystemParametersInfo(SPI_GETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
if (ai.iMinAnimate != 0)
{
ai.iMinAnimate = 0;
SystemParametersInfo(SPI_SETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
restoreAnimated = true;
}
// optionally move the window off-screen, or
// apply alpha using SetLayeredWindowAttributes()...
ShowWindow(hWnd, SW_SHOWNOACTIVATE);
}
// capture as needed ...
string path = "C:\\Users\\CAIO\\Desktop\\screenshot.jpg";
ULONG quality = 100;
SaveScreenshot(path, quality, hWnd);
if (wp.showCmd == SW_SHOWMINIMIZED)
{
SetWindowPlacement(hWnd, &wp);
// optionally remove alpha using SetLayeredWindowAttributes()...
if (restoreAnimated)
{
ai.iMinAnimate = 1;
SystemParametersInfo(SPI_SETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
}
}
return 0;
}
In her code there's restoreAnimation = true; and if (restoreAnimation) did he mean restoreAnimated?
With the code above it still shown the window for a sec, also the captured image is all black (maybe captured while minimized) or is not captured properly.
https://youtu.be/8b1wXxtaXsY?t=9
Sec 8 and 9 from the video you can see the window is being shown on the screen.
Suggestions?
did he mean restoreAnimated?
I think yes.
This code from #Remy only disables the animation effects when minimizing and restoring, the window will still be displayed for a short time when restoring. As the answer pointed out, you can use SetLayeredWindowAttributes to make the window nearly completely transparent(It should be noted that using SetLayeredWindowAttributes needs to ensure that hwnd has WS_EX_LAYERED style.) and then you will not see the window, but the operating system will.
In addition, the problem of incomplete window capture is because the window is not drawn completely, call UpdateWindow after ShowWindow works for me, it will send a WM_PAINT message to the window.
bool restoreAnimated = false;
BYTE Alph = 0;
LONG_PTR exstyle = 0;
if (wp.showCmd == SW_SHOWMINIMIZED)
{
ai.cbSize = sizeof(ANIMATIONINFO);
SystemParametersInfo(SPI_GETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
if (ai.iMinAnimate != 0)
{
ai.iMinAnimate = 0;
SystemParametersInfo(SPI_SETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
restoreAnimated = true;
}
// optionally move the window off-screen, or
// apply alpha using SetLayeredWindowAttributes()...
exstyle = GetWindowLongPtr(hWnd, GWL_EXSTYLE);
SetWindowLongPtr(hWnd, GWL_EXSTYLE, exstyle | WS_EX_LAYERED);
DWORD flag;
BOOL ret = GetLayeredWindowAttributes(hWnd, 0, &Alph, 0);
SetLayeredWindowAttributes(hWnd, 0, 1, LWA_ALPHA);
ShowWindow(hWnd, SW_SHOWNOACTIVATE);
UpdateWindow(hWnd);
}
// capture as needed ...
string path = "C:\\Users\\name\\Desktop\\screenshot.jpg";
ULONG quality = 100;
SaveScreenshot(path, quality, hWnd);
if (wp.showCmd == SW_SHOWMINIMIZED)
{
SetWindowPlacement(hWnd, &wp);
// optionally remove alpha using SetLayeredWindowAttributes()...
SetLayeredWindowAttributes(hWnd, 0, Alph, LWA_ALPHA);
SetWindowLongPtr(hWnd, GWL_EXSTYLE, exstyle);
if (restoreAnimated)
{
ai.iMinAnimate = 1;
SystemParametersInfo(SPI_SETANIMATION, sizeof(ANIMATIONINFO), &ai, 0);
}
}

C++ take snapshot bitmap returns black image

basically what i'm trying to achieve is a continuous flow of taking snapshots of specific part of a window. Up to now I've managed to take the screenshot and parse it pixelwise. However, all screenshots are black. Please help this newbie. No errors returned, FindWindow works and returns the correct window(to appwnd). I've been debugging this for the past 3 days and i'm out of ideas. Also i need to mention i am releasing the memory after using everything, to not clamp up my ram.I'm running Windows 10 last patch.
snippet of Code:
BOOL myfunction(appwnd){
RECT rcWindow;
GetWindowRect(appwnd, &rcWindow);
BITMAP bm;
HBITMAP hbmap;
HBITMAP hbmapold;
BITMAPINFO bmi;
HDC hdcShot;
//a while starts here(not the issue)
RECT rc;//get window rectangle
GetWindowRect(appwnd, &rc);
//creating bitmaps
HDC hdc = GetDC(0);
hdcShot = CreateCompatibleDC(hdc);
hbmap = CreateCompatibleBitmap(hdc, rc.right - rc.left, rc.bottom - rc.top);
//
if (!BitBlt(hdcShot, 0, 0, rc.right - rc.left, rc.bottom - rc.top, GetDC(0), rc.left, rc.right, SRCCOPY | CAPTUREBLT))
{
printf("bitblt failed");
system("pause");
}
SelectObject(hdcShot, hbmap);
if (!GetObject(hbmap, sizeof(BITMAP), (LPSTR)&bm))
{
printf("error at getobject");
system("pause");
return false;
}
int bitsperpixel = bm.bmBitsPixel;
if (bitsperpixel != 32 || bm.bmPlanes != 1)
{
printf("error at bitsperpixel/bm planes");
system("pause");
return false;
}
SetupBitmapInfo(bmi, bm.bmWidth, bm.bmHeight, bitsperpixel);
HDC hdcShotNew = CreateCompatibleDC(hdcShot);
HBITMAP hbmapNew = CreateCompatibleBitmap(hdcShot, rcWindow.right - rcWindow.left, rcWindow.bottom - rcWindow.top);
HBITMAP OldBmp = (HBITMAP)SelectObject(hdcShotNew, hbmapNew);
int width = rcWindow.right - rcWindow.left;
int height = rcWindow.bottom - rcWindow.top;
printf("\nwidth:%i", width);
printf("\nheight:%i", height);
//copy the screen using bitblt
BitBlt(hdcShotNew, 0, 0, width, height , hdcShot,0,0,SRCCOPY|CAPTUREBLT);
pPixels = new RGBQUAD[bm.bmWidth * bm.bmHeight];
if (!pPixels)
{
printf("ppixels failed");
return false;
}
SelectObject(hdcShotNew, OldBmp);
if (GetDIBits(hdcShotNew, hbmapNew, 0, bm.bmHeight, pPixels, &bmi, DIB_RGB_COLORS)==0)
{
ReleaseDC(appwnd, hdcShot);
printf("getdibits failed");
delete[] pPixels;
return false;
}
}
Snippet of printing pixels :
printf("\n%i,%i,%i", (int)pPixels[p].rgbRed, (int)pPixels[p].rgbGreen, (int)pPixels[p].rgbBlue);
all pixels are 0, always.
Snippet of SetupBitmapInfo:
void SetupBitmapInfo(BITMAPINFO& bmi, int bWidth, int bHeight, int bitsperpixel)
{
bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
bmi.bmiHeader.biWidth = bWidth;
bmi.bmiHeader.biHeight = bHeight;
bmi.bmiHeader.biPlanes = 1;
bmi.bmiHeader.biBitCount = bitsperpixel;
bmi.bmiHeader.biCompression = BI_RGB;
bmi.bmiHeader.biSizeImage = 0;
}

Capture pixel data from only a specified window

I want the code below to take a screenshot of a specified window only, becuse this way BitBlt is faster.
The code below takes a screenshot of a window, specified by the name of window, loads the pixel data in a buffer and then re-draws the picture on your screen just to prove the copying worked.
I'd like to take screenshots of browser windows like Google Chrome, but it doesn't seem to work. It draws a black rectangle on my screen with the correct dimensions of the window.
Seems to be working all the time with the window of Minecraft.
Also worked with the Tor Browser.
I noticed that after querying window info, minecraft's window had no child-windows, but when it didn't work with the others, all of them had multiple child-windows.
#include<iostream>
#include<Windows.h>
#include<vector>
using namespace std;
int main() {
HWND wnd = FindWindow(NULL, "Minecraft 1.15.1");//Name of window to be screenshoted
if (!wnd) {
std::cout << "e1\n";
std::cin.get();
return 0;
}
WINDOWINFO wi = { 0 };
wi.cbSize = sizeof(WINDOWINFO);
GetWindowInfo(wnd, &wi);
RECT rect;
GetWindowRect(wnd, &rect);
int width = wi.rcClient.right - wi.rcClient.left;
int height = wi.rcClient.bottom - wi.rcClient.top;
cout << width << height;
/////Fetch window info^^^^^^^^
BYTE* ScreenData = new BYTE[4 * width*height];
// copy screen to bitmap
HDC hScreen = GetWindowDC(wnd);
HDC hDC = CreateCompatibleDC(hScreen);
HBITMAP hBitmap = CreateCompatibleBitmap(hScreen, width, height);
HGDIOBJ old_obj = SelectObject(hDC, hBitmap);
BitBlt(hDC, 0, 0, width, height, hScreen, 0, 0, SRCCOPY);
SelectObject(hDC, old_obj);
BITMAPINFO bmi = { 0 };
bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
std::cout << GetDIBits(hDC, hBitmap, 0, 0, NULL, &bmi, DIB_RGB_COLORS)<<endl;
//std::cout << bmi.bmiHeader.biHeight<< " "<< bmi.bmiHeader.biWidth<<endl;
BYTE*buffer = new BYTE[4* bmi.bmiHeader.biHeight*bmi.bmiHeader.biWidth];
bmi.bmiHeader.biHeight *= -1;
std::cout<<GetDIBits(hDC, hBitmap, 0, bmi.bmiHeader.biHeight, buffer, &bmi, DIB_RGB_COLORS)<<endl;//DIB_PAL_COLORS
/////Load window pixels into a buffer^^^^^^^^
POINT p;
int r = 0;
int g = 0;
int b = 0;
int x = 0;
int y = 0;
HDC sc = GetDC(NULL);
COLORREF color;
while (true) {
if ((y*-1) == bmi.bmiHeader.biHeight+1 && x == bmi.bmiHeader.biWidth-1) { break; }
r = (int)buffer[4 * ((y*bmi.bmiHeader.biWidth) + x)+2];
g = (int)buffer[4 * ((y*bmi.bmiHeader.biWidth) + x)+1];
b = (int)buffer[4 * ((y*bmi.bmiHeader.biWidth) + x) ];
color = RGB(r, g, b);
SetPixel(sc, x, y, color);
x++;
if (x == bmi.bmiHeader.biWidth) {
y++;
x = 0;
}
}
/////Prove that the copying was successful and buffer is full^^^^^^^^
Sleep(5000);
std::cout << "fin\n";
std::cin.get();
return 0;
}
I think the problem is the order you're doing things.
Before you put the bitmap on the clipboard, you should select it out of your memory device context.
Once you put the bitmaps on the clipboard, you no longer own it, so you shouldn't try to delete it.
The best way to do that is probably to move your // clean up section before the // save bitmap to clipboard section and to eliminate your DelectObject(hBitmap) statement. So the tail end of your code should probably be:
BitBlt(hDC, 0, 0, width, height, hScreen, 0, 0, SRCCOPY);
// clean up
SelectObject(hDC, old_obj); // selects hBitmap out of hDC
DeleteDC(hDC);
ReleaseDC(NULL, hScreen);
// save bitmap to clipboard
OpenClipboard(NULL);
EmptyClipboard();
SetClipboardData(CF_BITMAP, hBitmap); // clipboard now owns the bitmap
CloseClipboard();
If you still have a problem after those changes, I would check the return value of the SetClipboardData call. If that's failing, GetLastError may give a clue.

An Aero caption title bar issue using DWM API on the windows 10

In order to draw the icon on the caption title bar, I have refereed this MSDN article and used DWM API to create my customize client area by calling DwmExtendFrameIntoClientArea.
my code:
CMainFrame::CMainFrame()
{
Gdiplus::GdiplusStartupInput gdiplusStartupInput;
ULONG_PTR gdiplusToken;
GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
BOOL fDwmEnabled = FALSE;
if (SUCCEEDED(DwmIsCompositionEnabled(&fDwmEnabled)))
TRACE0("DWM is enabled\n");
TCHAR szLogoPath[MAX_PATH];
GetModuleFileName ( GetModuleHandle(NULL), szLogoPath, _countof(szLogoPath) );
PathRemoveFileSpec ( szLogoPath );
PathAppend ( szLogoPath, _T("lena.bmp") );
m_pLogoImage = m_pLogoImage->FromFile ( CT2CW(szLogoPath) );
if(NULL == m_pLogoImage)
TRACE0("load image fail\n");
}
void CMainFrame::OnNcCalcSize(BOOL bCalcValidRects, NCCALCSIZE_PARAMS* lpncsp)
{
int xFrame = 2;
int yFrame = 2;
int nTHight = 30;
NCCALCSIZE_PARAMS * p;
RECT * rc;
RECT aRect;
RECT bRect;
RECT acRect;
p = (NCCALCSIZE_PARAMS *)lpncsp;
CopyRect(&bRect,&p->rgrc[1]);
CopyRect(&aRect,&p->rgrc[0]);
acRect.left = aRect.left + xFrame;
acRect.top = aRect.top - nTHight;
acRect.right = aRect.right - xFrame;
acRect.bottom = aRect.bottom - yFrame;
CopyRect(&p->rgrc[0],&acRect);
CopyRect(&p->rgrc[1],&aRect);
CopyRect(&p->rgrc[2],&bRect);
CFrameWnd::OnNcCalcSize(TRUE, lpncsp);
}
LRESULT CMainFrame::OnNcHitTest(CPoint p)
{
BOOL dwm_enabled = FALSE;
if (SUCCEEDED(DwmIsCompositionEnabled(&dwm_enabled)))
{
LRESULT result = 0;
if (!DwmDefWindowProc(m_hWnd, WM_NCHITTEST, 0, MAKELPARAM(p.x, p.y), &result))
result = HitTestNCA(m_hWnd, p);
if (result == HTNOWHERE && GetForegroundWindow() != this)
{
return HTCAPTION;
}
return result;
}
return CWnd::OnNcHitTest(p);
}
BOOL CMainFrame::PreCreateWindow(CREATESTRUCT& cs)
{
if(cs.hMenu!=NULL)
{
::DestroyMenu(cs.hMenu);
cs.hMenu = NULL ;
}
if( !CFrameWnd::PreCreateWindow(cs) )
return FALSE;
// TODO: Modify the Window class or styles here by modifying
// the CREATESTRUCT cs
cs.style = WS_CAPTION | WS_MINIMIZEBOX | WS_MAXIMIZEBOX | WS_OVERLAPPED| WS_SYSMENU | WS_THICKFRAME;
cs.dwExStyle &= ~WS_EX_CLIENTEDGE;
cs.lpszClass = AfxRegisterWndClass(0);
return TRUE;
}
void CMainFrame::OnActivate(UINT nState,CWnd* pWndOther,BOOL bMinimized )
{
CFrameWnd::OnActivate(nState,pWndOther,bMinimized);
BOOL fDwmEnabled = FALSE;
if (SUCCEEDED(DwmIsCompositionEnabled(&fDwmEnabled)))
{
if(nState == WA_ACTIVE )
{
MARGINS margins = {-1};
/*margins.cyTopHeight = 30;
margins.cxLeftWidth = 0;
margins.cxRightWidth = 0;
margins.cyBottomHeight = 0;*/
HRESULT hr = DwmExtendFrameIntoClientArea(m_hWnd, &margins);
if (!SUCCEEDED(hr))
TRACE0("Failed in DwmExtendFrameIntoClientArea\n");
}
}
}
void CMainFrame::OnNcPaint()
{
CFrameWnd::OnPaint();
CDC* dc = GetWindowDC();
RECT rcClient;
GetWindowRect(&rcClient);
dc->FillSolidRect(0,0,RECTWIDTH(rcClient),RECTHEIGHT(rcClient),RGB(255,0,0));
CPaintDC gdc(this); // device context for painting
Graphics gr(gdc.m_hDC);
gr.DrawImage ( m_pLogoImage, 0, 0 );
ReleaseDC(dc);
}
The result under Windows 7 is fine.
However, my window appears another unknown caption title bar under Windows 10.
I found out the unknown caption is caused by WS_THICKFRAME in the cs.style.
If I remove WS_THICKFRAME, the unknown cation bar will disappear, but I cannot resizing the border of my window. Furthermore, my program cannot capture the minimum, maximum and the close button message on my custom caption bar anymore.
I want to remove the unknown title bar without any side effect.
Does anyone could provide me a good solution or suggestion?
Best Regards,
When using DwmExtendFrameIntoClientArea, it means frame is extended in to client area. It is no longer in non-client area. So there is no need to override OnNcPaint, you can do all of the painting in OnPaint
void CMainFrame::OnPaint()
{
CPaintDC dc(this);
//paint titlebar area (this used to be the non-client area)
CRect rc;
GetClientRect(&rc);
rc.bottom = titlebar_height;
CDC memdc;
memdc.CreateCompatibleDC(&dc);
BITMAPINFOHEADER bmpInfoHeader = {
sizeof(BITMAPINFOHEADER), rc.Width(), -rc.Height(), 1, 32 };
HBITMAP hbitmap = CreateDIBSection(
dc, (BITMAPINFO*)(&bmpInfoHeader), DIB_RGB_COLORS, NULL, NULL, 0);
auto oldbitmap = memdc.SelectObject(hbitmap);
dc.BitBlt(0, 0, rc.Width(), rc.Height(), &memdc, 0, 0, SRCCOPY);
memdc.SelectObject(oldbitmap);
DeleteObject(hbitmap);
//begin normal paint
//The new client area begins below titlebar_height which we define earlier
GetClientRect(&rc);
rc.top = titlebar_height;
dc.FillSolidRect(&rc, RGB(0, 0, 255));
Gdiplus::Image *image = Gdiplus::Image::FromFile(L"file.jpg");
Gdiplus::Graphics gr(dc);
gr.DrawImage(image, 0, 0);
delete image;
}
Use a member variable CRect m_border to keep track of border's thickness. You can use AdjustWindowRectEx to find the thickness of the borders.
void CMainFrame::OnActivate(UINT nState, CWnd* pWndOther, BOOL bMinimized)
{
CFrameWnd::OnActivate(nState, pWndOther, bMinimized);
titlebar_height = 100;
//find border thickness
if (GetWindowLongPtr(m_hWnd, GWL_STYLE) & WS_THICKFRAME)
{
m_border = { 0,0,0,0 };
AdjustWindowRectEx(&m_border, GetWindowLongPtr(m_hWnd,
GWL_STYLE) & ~WS_CAPTION, FALSE, NULL);
m_border.left = abs(m_border.left);
m_border.top = abs(m_border.top);
}
else if (GetWindowLongPtr(m_hWnd, GWL_STYLE) & WS_BORDER)
{
m_border = { 1,1,1,1 };
}
else
{
m_border = { 0,0,0,0 };
}
//Extend frame in to client area
MARGINS margins = { 0 };
margins.cyTopHeight = titlebar_height; //<<=== *** edited
DwmExtendFrameIntoClientArea(m_hWnd, &margins);
SetWindowPos(NULL, 0, 0, 0, 0,
SWP_SHOWWINDOW | SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
}
m_border will be for example {7,7,7,7};
Allow Windows to do the painting on left, right, bottom border. The top border is the only one changed
void CMainFrame::OnNcCalcSize(BOOL validate, NCCALCSIZE_PARAMS FAR* lpncsp)
{
if (validate)
{
lpncsp->rgrc[0].left += m_border.left;
lpncsp->rgrc[0].right -= m_border.right;
lpncsp->rgrc[0].bottom -= m_border.bottom;
}
else
{
CFrameWnd::OnNcCalcSize(validate, lpncsp);
}
}
see also How to glow the minimum. maximum and close button?

How to glow the minimum. maximum and close button?

I followed below guide to create a custom Aero Frame using DWM API.
Custom Window Frame Using DWM
My work:
void CMainFrame::OnActivate(UINT nState,CWnd* pWndOther,BOOL bMinimized )
{
CFrameWnd::OnActivate(nState,pWndOther,bMinimized);
BOOL fDwmEnabled = FALSE;
if (SUCCEEDED(DwmIsCompositionEnabled(&fDwmEnabled)))
{
if(nState == WA_ACTIVE )
{
MARGINS margins ={-1};
HRESULT hr = DwmExtendFrameIntoClientArea(m_hWnd, &margins);
if (!SUCCEEDED(hr));
}
}
}
void CMainFrame::OnNcPaint(){
RECT rcClient;
GetWindowRect(&rcClient);
// Inform the application of the frame change.
SetWindowPos(
NULL,
rcClient.left, rcClient.top,
RECTWIDTH(rcClient), RECTHEIGHT(rcClient),
SWP_FRAMECHANGED);
CFrameWnd::OnNcPaint();
CDC* dc = GetWindowDC();
dc->FillSolidRect(0,0,RECTWIDTH(rcClient),RECTHEIGHT(rcClient),RGB(0,0,0));
}
LRESULT CMainFrame::OnNcHitTest(CPoint p)
{
LRESULT r ;
r = CFrameWnd::OnNcHitTest( p);
if(r == HTMINBUTTON || r == HTMAXBUTTON || r == HTCLOSE)
return r;
else
r = HitTestNCA(m_hWnd,p); // this function is direct copied from above link.
return r;
}
Result:
I found out the minimum, maximum and close button that will not be glowed when I move the mouse on these buttons.
General situation:
How to fix this problem?
Best Regards,
DwmDefWindowProc is required to handle caption buttons. From msdn:
For caption button hit testing, DWM provides the DwmDefWindowProc
function. To properly hit test the caption buttons in custom frame
scenarios, messages should first be passed to DwmDefWindowProc for
handling. DwmDefWindowProc returns TRUE if a message is handled and
FALSE if it is not. If the message is not handled by DwmDefWindowProc,
your application should handle the message itself or pass the message
onto DefWindowProc.
In MFC it can work out as follows:
LRESULT cframeWnd::OnNcHitTest(CPoint p)
{
BOOL dwm_enabled = FALSE;
if (SUCCEEDED(DwmIsCompositionEnabled(&dwm_enabled)))
{
LRESULT result = 0;
if (!DwmDefWindowProc(m_hWnd, WM_NCHITTEST, 0, MAKELPARAM(p.x, p.y), &result))
result = HitTestNCA(m_hWnd, p);
if (result == HTNOWHERE && GetForegroundWindow() != this)
{
return HTCAPTION;
}
return result;
}
return CWnd::OnNcHitTest(p);
}
I added a fix with GetForegroundWindow(), because the HitTestNCA function from MSDN example is wrong, it doesn't return HTCLIENT when it should. So when another window has focus, it won't switch windows upon mouse click in client area.
Also, there is a leak in OnNcPaint:
CDC* dc = GetWindowDC();
Whenever GetWindowDC() is called it should be followed by ReleaseDC. Or just use CWindowDC which has automatic cleanup. You don't actually need to override OnNcPaint because frame has been extended to "client area".
Here is a full example:
class cglassWnd : public CWnd
{
void OnNcCalcSize(BOOL, NCCALCSIZE_PARAMS FAR*);
LRESULT OnNcHitTest(CPoint p);
void OnNcMouseLeave();
int OnCreate(LPCREATESTRUCT lpCreateStruct);
void OnActivate(UINT state, CWnd* otherWnd, BOOL minimized);
void OnPaint();
CRect borders;
int titlebar_height;
DECLARE_MESSAGE_MAP()
public:
cglassWnd();
};
BEGIN_MESSAGE_MAP(cglassWnd, CWnd)
ON_WM_NCHITTEST()
ON_WM_NCCALCSIZE()
ON_WM_NCMOUSELEAVE()
ON_WM_ACTIVATE()
ON_WM_CREATE()
ON_WM_PAINT()
END_MESSAGE_MAP()
cglassWnd::cglassWnd()
{
BOOL dwm_enabled = FALSE;
DwmIsCompositionEnabled(&dwm_enabled);
if (!dwm_enabled)
TRACE("Error: don't use this class, add error handling...");
//modified height for the new title bar
titlebar_height = 60;
}
int cglassWnd::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
int res = CWnd::OnCreate(lpCreateStruct);
//find border thickness
borders = { 0,0,0,0 };
if (GetWindowLongPtr(m_hWnd, GWL_STYLE) & WS_THICKFRAME)
{
AdjustWindowRectEx(&borders,
GetWindowLongPtr(m_hWnd, GWL_STYLE) & ~WS_CAPTION, FALSE, NULL);
borders.left = abs(borders.left);
borders.top = abs(borders.top);
}
else if (GetWindowLongPtr(m_hWnd, GWL_STYLE) & WS_BORDER)
{
borders = { 1,1,1,1 };
}
//Extend caption in to client area
MARGINS margins = { 0 };
margins.cyTopHeight = titlebar_height;
DwmExtendFrameIntoClientArea(m_hWnd, &margins);
SetWindowPos(NULL, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
return res;
}
void cglassWnd::OnPaint()
{
CPaintDC dc(this);
//paint titlebar area (this used to be the non-client area)
CRect rc;
GetClientRect(&rc);
rc.bottom = titlebar_height;
//see MSDN reference for explanation of this code
//upside-down bitmap is for the sake of DrawThemeTextEx
CDC memdc;
memdc.CreateCompatibleDC(&dc);
BITMAPINFOHEADER infhdr = { sizeof(infhdr), rc.right, -rc.bottom, 1, 32 };
HBITMAP hbitmap = CreateDIBSection(dc,(BITMAPINFO*)(&infhdr),DIB_RGB_COLORS,0,0,0);
auto oldbitmap = memdc.SelectObject(hbitmap);
//do extra titlebar painting here
//for example put DrawThemeTextEx for window's name
dc.BitBlt(0, 0, rc.Width(), rc.Height(), &memdc, 0, 0, SRCCOPY);
memdc.SelectObject(oldbitmap);
DeleteObject(hbitmap);
//begin normal paint
//The new client area begins below titlebar_height which we define earlier
GetClientRect(&rc);
rc.top = titlebar_height;
dc.FillSolidRect(&rc, RGB(128, 128, 255));
}
void cglassWnd::OnNcCalcSize(BOOL validate, NCCALCSIZE_PARAMS FAR* sz)
{
if (validate)
{
sz->rgrc[0].left += borders.left;
sz->rgrc[0].right -= borders.right;
sz->rgrc[0].bottom -= borders.bottom;
}
else
{
CWnd::OnNcCalcSize(validate, sz);
}
}
LRESULT cglassWnd::OnNcHitTest(CPoint pt)
{
LRESULT result = 0;
//handle close/minimize/maximize button
if (DwmDefWindowProc(m_hWnd, WM_NCHITTEST, 0, MAKELPARAM(pt.x, pt.y), &result))
return result;
//cursor is over the frame or client area:
result = CWnd::OnNcHitTest(pt);
if (result == HTCLIENT)
{
ScreenToClient(&pt);
if (pt.y < borders.top) return HTTOP;
if (pt.y < titlebar_height) return HTCAPTION;
}
return result;
}
void cglassWnd::OnNcMouseLeave()
{
//This is for close/minimize/maximize/help buttons
LRESULT result;
DwmDefWindowProc(m_hWnd, WM_NCMOUSELEAVE, 0, 0, &result);
CWnd::OnNcMouseLeave();
}
void cglassWnd::OnActivate(UINT state, CWnd* otherWnd, BOOL minimized)
{
CWnd::OnActivate(state, otherWnd, minimized);
Invalidate(FALSE);
}